Flickering lights
 

Hey everyone,

I dunno if anyone is having or has ever had this problem, but recently I've noticed that my lights (headlights, dash, maplights,) are flickering. Not a whole lot,..very slightly, but i notice it. Mostly when I'm stopped at a light in idle. Its not a strong flicker, you kinda gotta focus on it to notice, but it is happening. I have good voltage at 14, and I dont really think its my alternator. It starts right up and stays charged. I dont think it's the battery because I just replaced it last August. Some feedback would be much appreciated.

Kas

RE: Flickering lights
 

I have the same issues with my 2000 Chevy Blazer!!! Would like to know what up as well!

RE: Flickering lights
 

hi"... my 01' blazer did the flickering day after i got it home. and just kept getting worse, as i did not have time to get it looked at. now, 2yrs. later, im having to replace the PCM,(250.00) i highly recommend you take time and get it looked at by a dealer, before this happens to you. they say it was the PCM all along, luckily it went out in my driveway, not 50 miles out in B.F.E.. i hope this helps...
johnny5

RE: Flickering lights
 

PCM?

RE: Flickering lights
 

Powertrain Control Module, located on pasenger side(under hood) mounted atop the coolant reservoir

RE: Flickering lights
 

First thing to check for is the sound system.Second thing to check is the A/c compressor. At night when my compressor turns on and off,I can tell. Third thing to check isapattern with therpms. if it does it sporadically,I don't know whatit is. I have never had that problemmyself, but I have worked in a shop long enough to have worked ona pcm module. Check voltage from the headlight fuse to negative battery post, play with the throttle a bit until it does it USE an analog meter... digital meters will not show the change as quick.

RE: Flickering lights
 

sory euro, i disagree, neither the radio or AC unit has to do with it. the Powertrain Control Module does. on the OBDII code scanner, the code came up as P1637 altenator L terminal circuit, which controls the ign. and lights, along with many other things. (finding this out as i go) will post more as i collect data

RE: Flickering lights
 

When using the defrost modes the A/C compressor will kick on and off, and the RPM will drop slightly for a brief period of time, sometimes making the lights dim... Heck, the volt meter twitches when the signal lights are on...

If it ONLY does it at idle, then that's most likely the issue, unless your throwing codes...

Try it with the heater system off, or turned to foot or face air blow only, no defrost or A/C, if it still does it, it's not the A/C cycling...